Need to figure out the total accuracy for a flow calibration system.

[USMCPMEL]

I do mass flow controllers using laminar flow elements and I am trying to figure out what my total system accuracy is?

[Kalrock]

You will have to include your pressure standard and probably your temperature standard as well.  The best thing to use if you have it is a bell system or even better dhi mol-blocs.

[USMCPMEL]

I was looking at the BIOS system not sure if anyone on here has any experience with that? It is the piston system there best is supposed to be +-.15 % accuracy.

[OlDave]

I don't have any experience with the ML-800 system that you are talking about, but I do have a good few years of working with the ML-500 under my belt. We bought our system just after the ML-500 came out and well before the ML-800 was available.

I love ours. From the best I can determine it is very repeatable and stable. Very nominal drift between calibration and what drift I've seen is almost always in the pressure sensor. I believe the ML-800 has an improved pressure sensor but I am not positive about that.

I've never liked laminar elements and I've always been skeptical of the mol-bloc, though I've never had any experience with it.

[dallanta]

  We had a flow computer.  The elements, temp, pressure......all was figured into the computer.  I liked it much better than figuring all that crap individually.